//clase biblioteca
$(document).ready(function() {
	$("#form").validate({
        rules: {
          isbn: "required",// simple rule, converted to {required:true}
          titulo: {// compound rule
          required: true,
          titulo: true
        },
        autor: {
        	autor: true
        },
        content {
          required: true
        }
        },
        messages: {
        	content: "Please enter a comment."
        }
      });
 });